The authors report on an enrichment program for minority students and its effect on those students' performance in the first year of medical school. The six-week preentrance enrichment program (PEP) offers a curriculum of basic science courses, study skills training, and a seminar on special topics, typically on sociomedical issues. From 1973 through 1984, 115 students who had been admitted to Boston University School of Medicine participated in the PEP prior to matriculation. The PEP participants had lower scores on the Medical College Admission Test than minority nonparticipants admitted to the medical school. Analysis of the first-year performance of PEP participants, however, indicated that the participants had significantly higher proportions of pass and honors grades than minority nonparticipants in two courses and slightly higher (though not significant) proportions of pass and honors grades in six other courses of the nine courses in the first-year curriculum. In a related study, preliminary analysis showed that participation in the PEP was one of the consistent predictors of overall academic performance during the first year. Questionnaires completed by participants before and after the program and their responses to a survey at the end of their first year of medical school indicated the participants felt they had gained benefits from the program that enhanced their academic adjustment.